Alternative reproductive tactics (ARTs), occur where members of one sex of a species have two or more strategies of obtaining fertilization. The tactics differ in behavioural approaches to reproduction, but also commonly differ in physiological and morphological traits. The round goby, Neogobius melanostomus, is a globally invasive species with male ARTs. How behaviour may influence invasiveness in round goby has been of recent interest, but researchers have not considered the role or impact that male ARTs may have. I compared guarder and sneaker male round goby, assessing differences in their boldness, activity, exploration, sociality, aggression, startle responses, and dispersal tendencies. Sneaker males were more bold, active, and explorative while guarder males were more aggressive. In addition, I studied whether more guarders or sneakers are caught in a population survey study and how variation in a common round goby trapping method, minnow traps, may create catch biases. Two commonly employed minnow trap models include a black vinyl plastic coated metal trap (black traps) and a galvanized metal steel trap (silver traps). I investigated whether these black and silver traps and baited (corn) and unbaited traps differ in terms of the numbers, ART ratios, and sizes of round goby captured. I found silver traps captured 1.7 times more round goby than black traps, while baited traps captured 3.4 times more round goby than unbaited traps. Baited traps captured larger round goby and tended to capture more guarders than unbaited traps. I also found black traps captured larger males, but there was no difference in the size of females captured. Taken together my results indicate that care needs to be applied when making estimates of round goby populations in terms of the types of individuals present and the trapping method used. / Thesis / Master of Science (MSc)

Yes / Sida requested the Helpdesk to present a ‘snapshot’ and analysis of the problem of conflict minerals in the Great Lakes region, and particularly of the Democratic Republic of Congo (DRC). In anticipation of instructions in the forthcoming country/results strategy for the DRC, Sida will use the report in order to identify possible Swedish efforts in the field. Sida requested that report should be presented with both a perspective on the Great Lakes region in general, as well as a more detailed analysis of the situation in DRC in a regional perspective.

<p> The nearshore morphology of sand beaches in the Great Lakes usually consists of a ridge and runnel unit in the shallow, inner portion of the nearshore zone and one or more longshore bar and trough units in the deeper, outer portion. These two sets of features are morphologically and genetically different and exhibit spatial and temporal variations indicating the relative importance of environmental factors in controlling the form of each. </p> <p> Ridges and runnels form and evolve in response to a combination of the controlling factors of wave and water level variations. Ridge formation occurs in response to a rapid decrease in wave energy and lowering of the water level during the subsiding period of a storm. Ridges, with heights of 0.04-0.40 m, take 5-10 days to migrate 10-30 m across an inner nearshore terrace toward the shore. Ridge migration produces laminations dipping at 20°-30° toward the shore. Ridge attachment to the shore produces an accretional berm composed of laminations dipping at about 5° toward the lake. </p> <p> An annual cycle of erosion and deposition occurs in the inner nearshore and foreshore zones and is due to seasonal wave energy and water level variations. Erosion occurs in spring and summer because of rising water levels while the deposition of planar laminations dipping at less than 5° toward the lake is caused by lower water levels and higher energy waves in autumn. </p> <p> Based on the analysis of over 100 echo sounder profiles of the outer nearshore zone of 7 beaches, longshore bar and trough morphologic properties (maximum depth of bar formation, number of bars, and bar amplitudes), are controlled by three main environmental factors (wave energy or surf base, nearshore slope, and sediment size). Bars are present at depths of 3.5 m and at distances of 500 m from the shore, the number of bars ranges up to 6, and bar amplitudes range up to 2 m. Surf base ranges from 3-6 m, slopes from 0.009-0.02, and mean sediment size from 1.85 Ø - 3.30 Ø. There is a good correlation between the slope and sediment size. Temporal variation in bar morphology during the summer period of study is small or insignificant. </p> <p> Individual longshore bars probably only approach, rather than attain, equilibrium forms because of the temporal flucuations in the environmental controls of wave energy and water level. The geometrical trend in all longshore bar systems for the bar amplitude and spacing between bars to increase with increasing depth and distance from the shoreline, suggests a wave energy dissipation process which is somewhat analogous to dampened oscillation. </p> / Thesis / Master of Science (MSc)

<p> Chemical data from atmospheric precipitation in the Upper Great Lakes region were collected on a monthly basis by various organizations from late 1972 to late 1975. The data for pairs of chemical parameters are regarded as simultaneously recorded time series and are analyzed by spectral analysis to bring out periodic components present in both time series and also to reflect the correlation and phase difference between the pairs of time series.</p> <p> The precipitation data have four major bands of periodicities: (1) a yearly cycle representing high and low atmospheric loadings in the summer and winter respectively with regards to Fe, PART, SO4 and P; (2) a 6 monthly period reflecting the four seasons of the year and affecting Fe, PART, P and pH; (3) a 9 monthly period for the heavy metals (Cu, Ni, Cd, Pb and Zn); and (4) 2 to 5 cycles/month periodicities caused by atmospheric turbulence and affecting all the parameters.</p> <p> The mining-smelting industry at Sudbury has been identified as a major point source of atmospheric emissions of acid, sulfate and the heavy metals, with the exception of iron, This is evident in view of the facts that the spectral intensities at the major periodicities decrease away from the mining-smelting centre; the strikingly high correlation and practically inphase relationship between Cu and Ni, and the 9 monthly period for the heavy metals which is associated with the industry.</p> / Thesis / Bachelor of Science (BSc)

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